#include<stdio.h>
#include <math.h>

int main()
{
    int a, b, c;
    scanf("%d %d %d", &a, &b, &c);
    if (a + b <= c || a + c <= b || b + c <= a)
    {
        printf("These sides do not correspond to a valid triangle");
    }
    else
    {
        double area, perimeter, s = (double)(a + b + c) / 2;
        area = sqrt(s * (s - a) * (s - b) * (s - c));
        perimeter = (double)(a + b + c);
        printf("area = %.2f; perimeter = %.2f", area, perimeter);
        
    }
    

    return 0;
}